[T3] Oil cooler seals.

[Jim Adney]

If you have leaky oil cooler seals, it will look like the area around 
the leak and down the side of the case has been washed off by the 
relatively clean oil that has come out of the leak. Tiny leaks may 
cause the accumulation of dirt, but those won't be important.

So the thing to look for is an area that is wet and cleaner than the 
rest of the dirty engine around it.

In all honesty, leaky oil pressure switches are much more common than 
leaky oil cooler seals.

You probably won't see a washed area around the governor cover 
because that is such a complicated area, but you will notice that the 
whole left side of the AT, and the CV  joint there, is dirtier than 
the corresponding parts on the right side. Leaky governor cover 
O-rings are extremely common. If yours has never been replaced, it's 
worth doing regardless. You'll probably be surprised to see how hard 
and oval it is.

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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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